This invention relates to a method of removing the inherent odor from Houttuynia cordata Thunb, and more particularly to a method of deodorizing Houttuynia cordata Thunb in which a heat-treatment and a fermentation are combined.
Houttuynia cordata Thunb, which has an inherent odor, has been widely known as Herb Houttuyniae from ancient times. The excellent medicinal effects thereof have been described in various publications relating to herb medicines.
For popular internal use, Houttuynia cordata Thunb is taken as a juice obtained from green leaves thereof or a decoction of a dried product of Houttuynia cordata Thunb collected before the flowering time thereof.
Although Houttuynia cordata Thunb has the aforementioned excellent medicinal effects and is established as an innocuous popular medicine, the untreated product thereof is difficult to drink due to its inherent odor and has poor storage stability. Additionally, the period of its utilization is limited to the growing period thereof.
The odor can be removed therefrom by drying in the shade, but the product thus dried must be decocted for a long time until the medicinal components are sufficiently extracted therefrom, which proves to be quite inconvenient.
It is well known that the inherent odor of Houttuynia cordata Thunb is due to lauric aldehyde, C.sub.11 H.sub.23 CHO, or its homologs, and is also known that these compounds can be removed by steam distillation.
Under these circumstances, the inventor found that the inherent odor of Houttuynia cordata Thunb can be removed therefrom by mashing or crushing green Houttuynia cordata Thunb and then fermenting the thus crushed matter with yeast inoculated therein.
However, since the aforementioned method allows easy contamination of the material, the final product may contain undesirable by-products derived from the contamination. When no additive is used, the final product may be unacceptable for internal use if such by-products are contained therein and in the past the product has often been discarded. If a germicidal agent or the like is used in the washing medium to remove sundry germs, the final product may contain undesirable impurities. Additionally, for the prevention of the entry of sundry germs, sterilizers or the like into the material, it is necessary in using said method to completely remove the wash water therefrom by letting the material dry or to wiping it completely after washing. This introduces troublesome operations.